Dissertations and Theses - Pathobiologyhttp://hdl.handle.net/2142/25441
Tue, 20 Mar 2018 02:26:33 GMT2018-03-20T02:26:33ZEvaluation of therapy for canine intracranial neoplasia using PAC-1, a novel and potent procaspase-3 activatorhttp://hdl.handle.net/2142/99088
Evaluation of therapy for canine intracranial neoplasia using PAC-1, a novel and potent procaspase-3 activator
Schlein, Lisa Janelle
Canine central nervous system tumors can develop deeply within the brain parenchyma, precluding surgical resection and limiting therapeutic options. PAC-1 is a novel, blood-brain barrier penetrant, pro-apoptotic small molecule activator of procaspase-3 (PC-3), with orphan drug status for the treatment of human glioblastoma multiforme. PC-3 is frequently overexpressed in malignantly transformed tissues, providing an opportunity to selectively induce apoptosis in cancer cells with dysregulated upstream apoptotic circuitry. This study evaluates the in vitro activity of PAC-1 against a panel of brain tumor cells, and the feasibility of combining PAC-1 with radiation therapy in an in vivo murine glioma model.
Immunohistochemical characterization of PC-3 was performed in 21 normal canine brains and approximately 700 canine and human intracranial neoplasms. Murine, canine, and human glioma cell lines were evaluated for PC-3 expression and in vitro sensitivity to PAC-1 and radiation.
PC-3 is overexpressed in canine intracranial neoplasms and high-grade human astrocytomas relative to normal brain tissues. Immortalized glioma cell lines show in vitro sensitivity to PAC-1 and radiation monotherapies at biologically relevant exposures. Murine gliomas appear to be sensitive to PAC-1 and radiation monotherapies, as well as to combination therapy with both PAC-1 and radiation therapy; however, murine study results are not statistically significant at this time.
Investigation of therapeutic approaches that combine PAC-1 with radiation therapy and/or temozolomide will further elucidate its therapeutic potential in murine models and canine patients.
Cancer; Brain cancer; Intracranial neoplasia; Canine neoplasia; Human neoplasia; Novel therapeutics; First procaspase-activating compound (PAC-1)
Fri, 14 Jul 2017 00:00:00 GMThttp://hdl.handle.net/2142/990882017-07-14T00:00:00ZSchlein, Lisa JanelleStudies on the interaction between porcine reproductive and respiratory syndrome virus and its natural host cellhttp://hdl.handle.net/2142/89219
Studies on the interaction between porcine reproductive and respiratory syndrome virus and its natural host cell
Chen, Wei Yu
Porcine reproductive and respiratory syndrome virus (PRRSV), an arterivirus, causes a costly global disease of swine. PRRSV infects their alveolar macrophages (AMΦ) resulting in an interstitial pneumonia. The ability of PRRSV to modulate the production of interferon (IFN)a and tumor necrosis factor (TNF)a by affected AMΦ is implicated in the virus’s pathogenesis. In this regard, infection of porcine AMΦ with PRRSV reduced by >50% the amount of IFN-α otherwise produced following the cells’ exposure to synthetic dsRNA. Interestingly, there was no corresponding impairment of the activation of either interferon regulatory factor 3 (IRF3) or signal transducer and activator of transcription 1 (STAT1), or of the transcription of the IFN-α, IFN-b, or IRF7 genes. Rather, the reduction correlated with the phosphorylation of eukaryotic translation initiation factor 2 (eIF2)a via the protein kinase RNA-like endoplasmic reticulum (ER) kinase (PERK) and the appearance of stress granules, indicating translational attenuation. Likewise, a TNF-α response to lipopolysaccharide (LPS) was inhibited when this toll-like receptor (TLR)4 agonist was introduced at 6 h post-infection, when peak TNF-α synthesis and eIF2α phosphorylation would coincide. In contrast, a synergistic TNFα response, due to NFkB activation via the inositol-requiring protein-1α (IRE-1α), was observed if LPS exposure occurred 4 h earlier enabling subsequent TNFα production to be unaffected by later eIF2α phosphorylation. Thus, representatives of two branches of the unfolded protein response (UPR) of AMΦ to PRRSV replication, IRE-1α and PERK, can enhance or suppress cytokine production by triggering the activation of NF-κB or eIF2a, respectively. It worth noting that the modulatory activities became critical when the PRRSV-infected cells were super-exposed to secondary stimulation of poly(I:C) or LPS. In which case exacerbated inflammation response in the lung will develop and produce significant morbidity and death. In the case of PRRSV infection alone, these cytokine responses such IFN-α are barely detected in spite of massive dsRNA produced in PRRSV-infected porcine AMΦ cells. As dsRNA is currently considered to be the most potent type I interferon (IFN) agonist, it has been suggested that sequestration of viral dsRNA may also help viruses evade host innate immune detection by reducing exposure of viral dsRNA to viral nucleic acids cytoplasmic sensors. This predicted type of immune evasion by virus-induced intracellular membrane structures had been confirmed for flaviviruses. By coupling a selective permeablization technique with immunostaining analysis, a positive correlation between the cytosolic exposure of virus dsRNA and a host type I IFN response was demonstrated. In this case, the extent of flavivirus dsRNA exposure was dependent on both the virus species and host cell type. Despite lacking definitive experimental evidence regarding members of the nidovirales family including arteriviruses and coronaviruses, it has been suggested that these viruses also utilize a similar immune evasion strategy. In this regard, the development of double membrane vesicle (DMV) structures has been associated with the activity of arterivirus nsp2 and its coronavirus equivalent, nsp3. Moreover, in our previous study, the arterivirus, porcine reproductive and respiratory syndrome virus (PRRSV) was shown to be incapable of inducing type I IFN synthesis upon infecting porcine alveolar macrophages. Thus, PRRSV appears to utilize a passive innate immunity evading mechanism. In the present study, in conjunction with the application of selective permeabilization, our immuno-staining results demonstrated for the first time that during PRRSV infection the viral dsRNA is sequestered inside intracellular membranes, which could prevent detection of virus dsRNA by host’s viral nucleic acid sensor. Evidence that it is indeed the case was provided by a laboratory PRRSV strain with a unique and deleterious mutation in the N-terminal region of NSP2, for which the virus losses the ability to sequester its dsRNA inside intracellular membrane structures and thus away from detection by viral nucleic acid sensors, resulting in a substantial type I IFN response upon infecting alveolar macrophages.
Alveolar Macrophages; Innate immunity; endoplasmic reticulum; Unfolded Protein Response; IRE1; eIF2; type I interferon; tumor necrosis factor alpha (TNFa); double stranded ribonucleic acid (dsRNA)
Tue, 01 Dec 2015 00:00:00 GMThttp://hdl.handle.net/2142/892192015-12-01T00:00:00ZChen, Wei YuThe variable contribution of larval habitats on the production of mosquitoes that transmit West Nile Virus: a landscape epidemiology approachhttp://hdl.handle.net/2142/88124
The variable contribution of larval habitats on the production of mosquitoes that transmit West Nile Virus: a landscape epidemiology approach
Rentschler, Trisha S
Many factors influence mosquito reproduction and abundance, including weather, landscape types, and habitat availability. Much of the focus of public health actions related to the reduction of mosquito-borne pathogens is on the reduction of mosquito populations through treatment or elimination of larval habitats associated with vector mosquitoes. West Nile virus is an important pathogen in North America. The objective of this study was to determine influences on Culex adult and larval mosquito population. Data for this study were collected during the summer of 2014 in a study region in suburban Chicago, Illinois. The data included a full identification of catch basin and natural standing water larval sites, weekly mosquito collections of larval and adult mosquitoes during an 18-week period, a more limited assessment of larval sites associated with containers near homes, and lawn watering activities. The analyses undertaken revealed that urban catch basins that have a higher percentage of vegetation of at least 3 meters can be expected to have more vector mosquito larvae; also warmer temperatures and less rainfall in a given week and the week prior will result in higher numbers of larvae during that week. Cemeteries in the study region tended to have more larvae in catch basins than either residential or industrial areas. One part of the study region had a spatial and temporal correlation between larval mosquitoes and adult mosquitoes, but other places had high adult abundance without a clear indication of the larval habitat contributing to that increase. It is important to consider multiple types of mosquito larval habitat, and while catch basins are an important breeding site, they are not the only source of adult mosquitoes in the region.
West Nile Virus; Culex Mosquitoes; Landscape Epidemiology; Spatial Epidemiology
Fri, 24 Jul 2015 00:00:00 GMThttp://hdl.handle.net/2142/881242015-07-24T00:00:00ZRentschler, Trisha SRole of Aryl Hydrocarbon Receptor in Circadian Rhythm: A Novel Pathway to Dioxin Toxicityhttp://hdl.handle.net/2142/87939
Role of Aryl Hydrocarbon Receptor in Circadian Rhythm: A Novel Pathway to Dioxin Toxicity
Mukai, Motoko
For decades, the study of aryl hydrocarbon receptor (AhR), a transcription factor and a member of the basic helix-loop-helix/Per-ARNT-Sim (bHLH-PAS) domain family, has been focused on its role in mediating adverse effects of some environmental contaminants, such as 2,3,7,8-tetrachlorodibenzo- p-dioxin (TCDD). However, a physiological role of AhR remains unknown. Many members of PAS domain family play a role in regulation of circadian rhythm; therefore the role of AhR in the circadian rhythm was investigated. First, to examine AhR as a basic component of the molecular clockwork, the circadian mRNA expression of AhR and its signaling targets in the suprachiasmatic nucleus (SCN), the master clock, and in the liver, a peripheral clock, were determined in mice. The circadian phenotype was also characterized in mice lacking AhR. Although not robust as some of the well-characterized clock genes, diurnal variation was observed in both tissues under light/darkness and constant darkness conditions. Second, the role of tryptophan (TRP) photoproducts that act as AhR agonists, were assessed in the light-regulation of circadian rhythm. Both exposure to light or treatment with TRP photoproducts activated AhR signaling in vitro and in vivo. Glutamate-induced phase shifting was inhibited by preincubation with FICZ in in vitro SCN slice cultures. Lastly, potential effects of TCDD on circadian rhythm were examined at the molecular and behavioral level. Exposure to TCDD affected circadian expression of clock genes and attenuated the light-induced phase shifts. Taken together, these results suggest that the AhR is potentially involved in regulating the molecular clockwork, especially in the light-regulatory pathway of circadian rhythm; exposure to environmental contaminants that interact with AhR may affect the ability of humans and animals to adjust their circadian rhythm to the external environment. Although further studies are necessary to decipher mechanisms of how AhR plays a role in circadian rhythm, this work opens new perspectives in both dioxin toxicology and chronobiology.
Biology, Physiology
Sun, 01 Jan 2006 00:00:00 GMThttp://hdl.handle.net/2142/879392006-01-01T00:00:00ZMukai, MotokoPseudorabies Virus Infection of Porcine Peripheral Blood Leukocyteshttp://hdl.handle.net/2142/87647
Pseudorabies Virus Infection of Porcine Peripheral Blood Leukocytes
Page, Gregory Raymond
Pseudorabies virus (PRV) is an alphaherpesvirus of swine that causes significant morbidity in adult populations, morbidity and mortality in young pigs, and economic losses to the swine industry each year. Evidence suggests that PRV causes immunosuppression in infected swine with resultant risk of secondary viral and bacterial infections. Virus was recovered from peripheral blood leukocytes (PBL) collected from infected swine, as well as from immune cells isolated from various lymphoid tissues (e.g., lymph node, tonsil, thymus). Lymphocytes stimulated with T cell mitogens, but not B cell mitogens, were permissive to PRV infection in vitro, as evidenced by the expression of PRV antigens on the surface of these cells and by the production of low titers of infectious PRV. Monocytes were highly permissive to PRV infection in vitro, and 75% of monocytes in culture expressed viral antigens on the cell surface. T lymphoblasts are also permissive, and several important functional phenotypes expressed PRV surface antigens after infection. Twenty percent of CD2-bearing lymphoblasts (total T cells) expressed viral antigens on the cell surface after infection, including 15% of CD4-bearing lymphoblasts (helper T cells) and 13% of CD8-bearing lymphoblasts (cytotoxic T cells and natural killer cells). Up to 90% of cells in culture of an immortal lymphoblastoid cell line expressed viral antigens on the cell surface after infection. Both purified CD4-bearing lymphoblasts and purified CD8-bearing lymphoblasts, as well as the lymphoblastoid cell line, replicated PRV to low titers after infection. These findings suggest that evidence of immunosuppression in PRV-infected swine may be the result of direct infection of lymphocyte effectors of immune function. Infected leukocytes may also play a role in dissemination of PRV to organ sites distant from the initial site of infection (i.e., beyond the respiratory tract).
Health Sciences, Immunology
Sat, 01 Jan 2000 00:00:00 GMThttp://hdl.handle.net/2142/876472000-01-01T00:00:00ZPage, Gregory RaymondCryptosporidium Parvum Microbial Adhesion: Interactions Between Sporozoites and Host Cellshttp://hdl.handle.net/2142/87645
Cryptosporidium Parvum Microbial Adhesion: Interactions Between Sporozoites and Host Cells
Johnson, Julie Kristine
Cryptosporidium parvum is a significant protozoal pathogen of both humans and animals worldwide. Since little is known about the mechanisms of attachment and invasion of C. parvum sporozoites to host cells, our goal was to elucidate the mechanism of sporozoite recognition of receptors on the host cell membrane. Knowledge of these mechanisms may allow for novel therapeutic strategies for cryptosporidiosis. An in vitro cell suspension binding assay was developed and used to investigate binding between C. parvum sporozoites and host cells. Morphologic features of binding events visualized with this assay were identical to those described in natural infections. A variety of glycoconjugates, as well as plasma membrane vesicles, were screened for their ability to block C. parvum sporozoite binding to MDBK cells. Of the naturally occurring and synthetic glycoconjugates tested, only mucins inhibited binding between sporozoites and host cells. Plasma membrane vesicles, which represent intact portions of plasma membrane, exhibited dose-dependent inhibition of binding. Solubilization of inhibitory activity from aqueous extracts of MDBK cells, followed by purification with ion exchange chromatography, was attempted. Complete solubility of inhibitory activity in aqueous buffers was not achieved, and inhibitory activity was polydispersed following ion exchange chromatography. The inhibitory activity of MDBK cell extracts was resistant to heat, protease digestion, and glycosidase treatment, suggesting it may be lipid or a lipid-like component. Organic solvent extraction of MDBK cells and bovine mucosa resulted in recovery of inhibitory activity. Purification of these extracts by preparative thin-layer chromatography yielded two major inhibitory fractions, a polar lipid fraction and a nonpolar fraction, with the nonpolar fraction containing the major inhibitory activity. This lipid was purified from bovine small intestinal mucosa by semipreparative HPLC followed by preparative HPTLC. Biochemical analyses, TLC staining techniques, mass spectrometry, and elemental analysis were used to partially characterize this lipid. The results of these analyses indicate the isolation of a small molecular weight, nonsaponifiable lipid lacking carbohydrate moieties, nitrogen, and phosphorus. Recognition of this novel intestinal membrane lipid by C. parvum sporozoites likely represents an early event in the overall adhesion and invasion process.
Agriculture, Animal Pathology
Sat, 01 Jan 2000 00:00:00 GMThttp://hdl.handle.net/2142/876452000-01-01T00:00:00ZJohnson, Julie KristinePredicting the Risk of Lyme Disease in the Midwestern United States: Surveillance Methods, Environmental Determinants, and Geographic Distributionhttp://hdl.handle.net/2142/87644
Predicting the Risk of Lyme Disease in the Midwestern United States: Surveillance Methods, Environmental Determinants, and Geographic Distribution
Guerra, Marta Alicia
The use of a combination of surveillance methods is the most effective way of assessing Lyme disease risk in an area where risk is unknown. Significant environmental determinants can be identified using a GIS, and a risk map can be generated to detect unknown endemic areas and to predict where new foci may develop.
Health Sciences, Public Health
Sat, 01 Jan 2000 00:00:00 GMThttp://hdl.handle.net/2142/876442000-01-01T00:00:00ZGuerra, Marta AliciaThe Illinois Pseudorabies Eradication Program and Factors Associated With Selection of Intervention Strategies and Success in Eradicationhttp://hdl.handle.net/2142/87643
The Illinois Pseudorabies Eradication Program and Factors Associated With Selection of Intervention Strategies and Success in Eradication
Siegel, Arthur Marc
Positive autocorrelation was found to exist for the spatial distribution of quarantines among Illinois counties. This finding indicates that counties in close proximity tend to have similar numbers of herds under PrV quarantine. It was also found that space-time interaction or clustering was present for the date of quarantine initiation and the date of quarantine release. These findings indicate that PrV quarantines occur on a regional basis and close in time. Therefore, PrV eradication should be dealt with on a community or regional basis for greatest efficiency.
Agriculture, Animal Pathology
Fri, 01 Jan 1999 00:00:00 GMThttp://hdl.handle.net/2142/876431999-01-01T00:00:00ZSiegel, Arthur MarcEvaluation of the Effectiveness of a Feline Toxoplasma Vaccine in Reducing the Exposure of Swine to Toxoplasma Gondiihttp://hdl.handle.net/2142/87646
Evaluation of the Effectiveness of a Feline Toxoplasma Vaccine in Reducing the Exposure of Swine to Toxoplasma Gondii
Mateus-Pinilla, Nohra Esperanza
The second study used a deterministic dynamic computer simulation model of the transmission of T. gondii in the swine farm ecosystem in a factorial experimental design to test the following hypotheses. T. gondii infection in finishing pigs decreases with (1) vaccination of susceptible cats, (2) increased cat capture rate (for vaccination), (3) decreased number of cats, (4) decreased T. gondii prevalence in cats, and (5) decreased oocyst survival time. Simulations were run for 10 years, with a weekly interval. Elimination of T. gondii in finishing pigs increased with a decrease in oocysts survival and a decrease in the number of cats in the farm. T. gondii prevalence in finishing pigs decreased with a decrease in the number of cats, a decrease in oocyst survival time, vaccinating and using an optimized vaccination schedule. Initial T. gondii prevalence in cats had no effect on outcome. Vaccination had less impact in decreasing T. gondii infection in finishing pigs than a decrease in the number of farm cats.
Agriculture, Animal Pathology
Sat, 01 Jan 2000 00:00:00 GMThttp://hdl.handle.net/2142/876462000-01-01T00:00:00ZMateus-Pinilla, Nohra EsperanzaElicitation and Characterization of Antibodies With Idiotypic (Ab1) and Anti-Idiotypic (Ab2) Reactivity: Epibodieshttp://hdl.handle.net/2142/87642
Elicitation and Characterization of Antibodies With Idiotypic (Ab1) and Anti-Idiotypic (Ab2) Reactivity: Epibodies
Muhumuza, Luke
Studies of the regulatory idiotypic network have routinely assayed idiotypic (Ab1) and anti-idiotypic (Ab2) levels in the immune response. This work is a follow up of a previous study in which Ab1 and Ab2 responses to the hapten DNP were found to be similar in terms of magnitude and kinetics following immunization. In this study, spleen cells of mice immunized with different dinitrophenylated carriers were fused with myeloma cells to generate monoclonal antibodies. These were assayed by ELISA for Ab1 and Ab2 reactivity. It was found that some of antibodies bound only the antigen, others bound both antigen and idiotypic antibody, while others bound both antigen and idiotypic antibody, in addition to a wide range of unrelated antigens commonly used to demonstrate polyreactivity. Which type of reactivity depended on the carrier used, as well as the intensity of immunization. The monoclonal antibodies which bound only the antigen and idiotypic antibody (epibodies) were further characterized for such properties as specificity of binding, inhibition by various inhibitors, self-binding, and affinity of binding. The epibodies generated were specific for the binding site of the idiotypic antibody used for coating ELISA plates, and were inhibited by both hapten and idiotypic antibody. They had a potential for self-binding and had moderately high affinity for both antigen and idiotypic antibody. In this study, epibodies were therefore elicited in a conventional immune response.
Biology, Veterinary Science
Wed, 01 Jan 1997 00:00:00 GMThttp://hdl.handle.net/2142/876421997-01-01T00:00:00ZMuhumuza, Luke